This invention is directed to a separated ion source which has geometry which employs the same magnetic field source for both ion production and ion separation.
Prior structures were comprised of separate functional components which were connected together to form the ion beam line. An ion source was used and it had its own magnetic field structure if such was required for the production of the ion beam. Ion separation downstream from the ion source required additional separation components. Due to the separate-element approach to the problems, such a structure is unnecessarily long and complex. These disadvantages are particularly bad in the case of high current low energy beams because severe space charge expansion occurs in the region between the ion source and separator. Attempts to locate the separator just downstream of the ion source were unsuccessful because the magnetic fields interferred. That is, the axial magnetic field in the ion source was disturbed by the transverse magnetic field of the separator.